Article Categories
- All Categories
-
Data Structure
-
Networking
-
RDBMS
-
Operating System
-
Java
-
MS Excel
-
iOS
-
HTML
-
CSS
-
Android
-
Python
-
C Programming
-
C++
-
C#
-
MongoDB
-
MySQL
-
Javascript
-
PHP
Articles on Trending Technologies
Technical articles with clear explanations and examples
How to display the values of two columns of an R data frame separately in a plot?
In general, the scatterplot is used to visualize the relationship between two columns of an R data frame but if we want to display the two columns separately not as a pair then we need to use matplot function. This function will create a plot for all the values in the two columns and represent them by their column number.Consider the below data frame −Example Live Demoset.seed(222) x
Read MoreHow to standardize matrix elements in R?
The standardization is the process of converting a value to another value so that the mean of the set of values from which the original value was taken becomes zero and the standard deviation becomes one. To standardize matrix elements, we can use data.Normalization function of clusterSim package but we need to make sure that we set the type argument to n1 because that corresponds to standardization with mean zero and standard deviation 1.Loading clusterSim package −library("clusterSim")Example Live DemoM1
Read MoreHow to change a data frame with comma separated values in columns to multiple columns in R?
Mostly, we need to import the data from an outside source in R environment for analysis and these data can be recorded as comma separated values that represent rows. If we want to create the columns for the comma separated values then cSplit function of splitstackshape package can be used. In the below example, we have created a data frame with comma separated values then splitting those values as single value in each column.Consider the below data frame −Example Live Demodf=data.frame(x=apply(matrix(rpois(200, 10), 20, 10), 1, paste, collapse=", ")) dfoutputx 1 8, 12, 7, 12, 10, 8, 11, 6, 8, 7 2 ...
Read MoreHow to add a mathematical expression in axis label in a plot created by using plot function in R?
When we create a plot using plot function in R, the axes titles are either chosen by R automatically based on the vectors passed through the function or we can use ylab or xlab for particular axes. To add a mathematical expression in an axis label, we can use title function with expression function to define the mathematical expression.Consider the below vectors and create scatterplot between the two −Exampleset.seed(111) x
Read MoreHow to create a black and white word cloud in R?
According to Google, a word cloud is an image composed of words used in a particular text or subject, in which the size of each word indicates its frequency or importance. In R, we can create word cloud by using wordcloud function of wordcloud package. So, we have the same name of the function as the package, thus we should not get confused by it.Loading wordcloud package and creating a wordcloud −library("wordcloud") x
Read MoreHow to convert the repeated elements of strings in a vector to unique elements in R?
When we have repeated elements of strings and we want to use them as factor levels then it is okay but if we want to treat them individually then it is better to make each value a unique element. To do this, we can use make.unique function. For example, if we have a vector x that contains repeated string values then to make them unique, we can use make.unique(x).Example Live Demox1
Read MoreHow to subtract one data frame from another in R?
If we have two data frames with same number of columns of same data type and equal number of rows then we might want to find the difference between the corresponding values of the data frames. To do this, we simply need to use minus sign. For example, if we have data-frames df1 and df2 then the subtraction can be found as df1-df2.Consider the below data frame −Example Live Demox1
Read MoreHow to create a list of an unordered combination of elements in a string vector in R?
An unordered combination of elements means that the combination of the values in a way that does not make any particular arrangement. For example, if we have three values one, two, and three then they can be arranged in the following way which is unordered −"one" "two" "three" "one" "two" "one" three" "two" "three" "one" "two" "three"Example Live Demox
Read MoreHow to check whether a year or a vector of years is leap year or not in R?
Almost everyone knows that a leap has 366 instead of 365 days and it occurs once in four years. If we want to check whether a particular year is a leap year or in a range of years which years correspond to leap year then we can use leap_year function of leap year. The length function can be used with the year value and if the output is 1 then it will be a leap year otherwise the output will be 0 which refers to the non-leap year.Loading lubridate package −Examplelibrary("lubridate") year1
Read MoreHow to change the title of a graph to italic created by using plot function in R?
If a graph is created by specifying main title of the plot using the plot function then the default font is plain text. We might want to change the style of the font to italic so that the title gets a little more attraction of the viewers. This can be done by using font.main argument with plot function. The value 4 of font.main refers to the bold italic font and if we want to make it bold then we can use the value 3.Consider the below vectors and create the scatterplot between the two with title of the plot −Examplex
Read More